Fence post removal can be a laborious and time-consuming task. In most cases, a very large pulling force must be applied to the fence post in order to remove it from an installed condition in the ground. Removal of fence posts is further complicated by the fact that it is difficult to securely grasp certain fence posts, either manually or using tools.
In order to overcome the challenges presented by fence post removal, a large number of tools have been previously proposed. The great majority of these tools rely on manual application of force in order to remove a fence post. Such tools may be suitable for removal of a small number of posts but are not well-suited for larger jobs, as the workers tasked with removing the fence posts will quickly become fatigued. A limited number of previous designs have attempted to apply some manner of powered lifting means to removal of a fence post. Some of these designs rely on leverage induced by rotation of a sleeve in which a pole is inserted. Such devices have no active clamping mechanisms but rather require that torque be applied to the fence post in order to grip the post and remove it from the ground. This requires a lifting means that can produce a very high degree of lifting force. As a result, the post may become damaged during removal to an extent that prevents reuse of the post.
Other designs have attempted to grip posts by use of a pawl-type arrangement or other mechanical catch that engages an irregular surface on the post itself. These designs are particularly adapted to remove fence posts of the well-known “T” post design. Such fence posts have a T-shaped cross-section and projections on one surface to which fencing can be attached. The projections provide an engagement surface for the pawl-type engaging member. In these designs, release of the fence post with respect to the tool may require operation of a release mechanism that causes the pawl-type engagement structure to disengage from the fence post. The need for manual disengagement, as well as the complexity associated with such a design, serve as impediments to widespread adoption and use of such a design.
It would be desirable to have a fence post extractor that could be operated by a powered lifting means, is capable of engaging the fence post without the need for application of a high degree of torque or lifting force, and may be released from engagement with the fence post without operation of a separate release mechanism.